Wiring sheet, electric distribution box and method of cutting wires

ABSTRACT

A wiring sheet for installing a plurality of wires thereon includes a side plate portion, at which end portions of the wires forming circuits are collectively disposed.

BACKGROUND OF THE INVENTION

[0001] This invention relates to a wiring sheet and an electricdistribution box in which for example, an electronic unit (electroniccontrol device) for a vehicle is mounted, and a wire-cutting operationcan be easily effected, and the invention also relates to a method ofcutting wire.

[0002]FIG. 13 shows one related electric distribution box.

[0003] This electric distribution box 501 includes an upper cover 502made of a synthetic resin, a lower cover 503 (i.e., a distribution boxbody), and a wire wiring board 504 and a bus bar wiring board 505 whichare received between the two covers 502 and 503 in a stacked manner.

[0004] The wire wiring board 504 includes an insulating board portion506 made of a synthetic resin, a plurality of insulating sheathed wires507 laid on a surface of the insulating board portion 506, and terminals508 which extend through the insulating board portion 506, and arepress-contacted respectively with wires 507. A press-contacting portion508 a is formed at one end of the terminal 508 while a male tab-likeelectrical contact portion 508 b is formed at the other end thereof.

[0005] The bus bar wiring board 505 includes an insulating board portion509, and a plurality of bus bars 510 installed on a surface of theinsulating board portion 509. The bus bar 510 has an integral maletab-like terminal 511 extending upwardly therefrom or an integral maletab-like terminal 511 extending downwardly therefrom.

[0006] The terminals 508 and 511 project into corresponding housings 512and 513 formed at the upper cover 502 and the lower cover 503, and theterminals 508 and 511 are combined with the housings 512 and 513 to formconnectors. Connectors (not shown) of external wire harnesses areconnected to these connectors.

[0007] In the above related electric distribution box 501, however, thewires 507, installed on the wiring board 504, need to be cut one by one,using a tool such for example as a nipper (not shown), and the operationfor cutting the wires 507 was not effected efficiently. And besides,there was a fear that the worker forget to cut one or more wires 507, sothat a predetermined circuit failed to be formed.

[0008] In view of the above circumstances, it is an object of thisinvention to provide a wiring sheet, an electric distribution box, and amethod of cutting wire, in which a wire-cutting operation can be carriedout easily, and troubles, such as the failure to cut a wire, areprevented during the wire-cutting process, thereby enhancing thereliability.

SUMMARY OF THE INVENTION

[0009] In order to achieve the above object, according to the presentinvention, there is provided a wiring sheet for installing a pluralityof wires thereon, comprising:

[0010] a side plate portion, at which end portions of the wires formingcircuits ar collectively disposed.

[0011] With this construction, for example, there can be easily carriedout an operation in which the wire is cut along the side plate portionof the wiring sheet, so that the circuits, provided with the pluralityof wires, are formed at the wiring sheet. Therefore, the circuits,provided with the plurality of wires, can be easily and rapidly formedat the wiring sheet, and therefore there is provided the wiring sheetwhich is excellent in productivity.

[0012] Preferably, a plurality of mounting portions are formed on theside plate portion. The end portions of the wires are fixed to theplurality of mounting portions, respectively.

[0013] With this construction, the end portions of the wires arepositively kept retained respectively in the mounting portions providedat the one side plate portion of the wiring sheet. And besides, forexample, the wire cutting operation can be carried out at the one sideplate portion of the wiring sheet, and by doing so, the wire-cuttingoperation can be carried out rapidly.

[0014] Preferably, wherein each of the mounting portions has a grooveshape for holding the end portion of each of the wires.

[0015] With this construction, the wires are positively fixed to the oneside plate portion of the wiring sheet over a long period of time. Andbesides, when the wire is to be cut so as to form the circuits (providedwith the plurality of wires) at the wiring sheet, the wire will not beflexed, thereby avoiding a trouble such as the failure to cut the wire,and as a result the circuits, provided with the plurality of wires, areeasily and positively formed at the wiring sheet

[0016] Preferably, the wiring sheet further comprises a board portionplaced horizontally. The side plate portion is vertically formed at aperipheral portion of the board portion. The end portions of the wiresare disposed outside of the board portion and the side plate portion ofthe wiring sheet.

[0017] With this construction; the end portions of the wires, are notdisposed on the base plate portion of the wiring sheet. Therefore, theend portions of the wires will not contact other parts on the wiringsheet, thereby preventing electrical troubles such as theshort-circuiting in the circuits of the wiring sheet, and therefore thereliability of the wiring sheets is enhanced.

[0018] According to the present invention, there is also provided anelectric distribution box, comprising:

[0019] a wiring sheet for installing a plurality of wires thereon,including:

[0020] a side plate portion, at which end portions of the wires forminga circuit are collectively disposed; and

[0021] a main body, housing the wiring sheet therein, and having a sidewall for protecting the end portions of the plurality of wires exposedfrom the side plate portion.

[0022] With this construction, the end portions of the plurality ofwires will not be exposed to the exterior of the main body. Therefore,electrical troubles will not occur in the electric distribution box, andthe reliability of the electric distribution box is enhanced.

[0023] Preferably, the wiring sheet includes a board portion placedhorizontally. The side plate portion is vertically formed at aperipheral portion of the board portion. The end portions of the wiresare disposed outside of the board portion and the side plate portion ofthe wiring sheet.

[0024] With this construction, the end portions of the wires, will notbe exposed to the exterior of the base wall and side wall of theelectric distribution box. Therefore, electrical troubles will not occurin the electric distribution box, and there can be provided the electricdistribution box of enhanced reliability.

[0025] Preferably, a plurality of mounting portions are formed on theside plate portion. The end portions of the wires are fixed to theplurality of mounting portions, respectively.

[0026] Preferably, each of the mounting portions has a groove forholding the end portion of each of the wire.

[0027] Preferably, the wiring sheet includes a board portion placedhorizontally. The side plate portion is vertically formed at aperipheral portion of the board portion. The end portions of the wiresare disposed outside of the board portion and the side plate portion ofthe wiring sheet.

[0028] According to the present invention, there is also provided amethod of cutting wires, comprising the steps of:

[0029] installing the wires on a wiring sheet;

[0030] fixing portions of the wire to a side plate portion of the wiringsheet; and

[0031] cutting the portions of the fixed wire so as to divide into aplurality of end portions of the wires so that circuits formed by thecut wires are provided.

[0032] In the above method, the wire is installed on the wiring sheet,and is fixed to the wiring sheet, and therefore the wire is positivelyfixed to the wiring sheet. And, the portions of the wire are fixed tothe side plate portion of the wiring sheet, and the wire is divided intothe plurality of wires by cutting the portions of the wire, andtherefore the portions of the wire are easily cut. And besides, withthis wire-cutting method, the portions of the wire are out efficientlyand rapidly. Therefore, the efficiency of the process of cutting thewire is enhanced.

[0033] Preferably, a plurality of mounting portions are formed on theside plate portion. The end portions of the wires are fixed to theplurality of mounting portions, respectively.

[0034] In the above method, the mounting portions, corresponding to theportions of the wire, are provided at the one side plate portion of thewiring sheet, and the portions of the wire are fixed to the mountingportions, respectively, and therefore the portions of the wire arepositively mounted at the one side plate portion of the wiring sheet.And besides, the portions of the wire are fixed to the mounting portionsprovided at the one side plate portion of the wiring sheet, and in thiscondition the portions of the wire are cut, and therefore thewire-cutting operation can be carried out at the mounting portions ofthe one side plate portion of the wiring sheet. Therefore, the wirecutting operation does not need to be carried out at various portions ofthe wiring sheet, and therefore the wire-cutting operation is carriedout positively and rapidly.

[0035] Preferably, each of the mounting portions has a groove forholding the end portion of each of the wires.

[0036] With the above method, the portions of the wire are positivelyfixed to the one side plate portion of the wiring sheet. Therefore, atthe time of cutting the portions of the wire, the portions of the wireare prevented from shaking relative to the wiring sheet, and thewire-cutting operation is carried out easily and positively.

[0037] Preferably, the wiring sheet has a board portion placedhorizontally. The side plate portion is vertically formed at aperipheral portion of the board portion. The end portions of the wiresare disposed outside of the board portion and the side plate portion ofthe wiring sheet.

[0038] In the above method, the wire-cutting operation can be carriedout easily. For example, when the wire-cutting operation is to becarried out by the use of a cutting tool, the cutting tool is movedalong the outer side of the side plate portion of the wiring sheet, andas a result the portions of the wire, disposed at the outside of theside plate portion of the wiring sheet, are easily cut. Therefore, thewire-cutting process of cutting is carried out rapidly.

[0039] Preferably, the method further comprises the steps of:

[0040] housing the wiring sheet in a main body of an electricdistribution box after performing the fixing step; and

[0041] fixing portions of the wires to a side wall of the main body.

[0042] In the above method, the portions of the wire are positivelyfixed to the wiring sheet and the main body. Therefore, when cutting theportions of the wire, the portions of the wire are prevented from beingmuch flexed, so that it is not difficult to effect the operation forcutting the portions of the wire. Therefore, the portions of the wire,fixed to the wiring sheet and the main body, are held in such acondition that these wire portions can be cut positively and easily.

[0043] Preferably, the portions of the wire extended to the outside ofthe side plate portion are cut simultaneously in the cutting step sothat circuits formed by the cut wires are provided.

[0044] In the above method, troubles, such as the failure to cut thewire, are prevented at the time of cutting the wire. Therefore, thecircuits, provided with the plurality of wires, can be positively formedat the wiring sheet.

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above objects and advantages of the present invention willbecome more apparent by describing in detail preferred exemplaryembodiments thereof with reference to the accompanying drawings,wherein:

[0046]FIG. 1 is a perspective view of one preferred embodiment of theinvention, showing wiring sheets and a method of cutting wire;

[0047]FIG. 2 is an enlarged perspective view showing a condition inwhich end portions of wires are disposed at side plates of the wiringsheets of FIG. 1;

[0048]FIGS. 3A and 3B are views explanatory of the process ofpress-contacting a wiring member with a press-contacting terminal, andFIG. 3A is a view showing a condition before the wiring member ispress-contacted with the press-contacting terminal, and FIG. 3B is aview showing a condition after the wiring member is press-contacted withthe press-contacting terminal;

[0049]FIG. 4 is a perspective view showing a condition in which ahousing member is mounted on the upper wiring sheet;

[0050]FIG. 5 is an enlarged perspective view showing a condition inwhich the end portions of the wires are disposed at the side plates ofthe wiring sheets;

[0051]FIG. 6 is a perspective view showing one preferred embodiment ofan electric distribution box of the invention;

[0052]FIG. 7 is a perspective view showing an outer side of a cover;

[0053]FIG. 8 is a perspective view showing an inner side of the cover;

[0054]FIG. 9 is a perspective view showing the electric distribution boxin its assembled condition;

[0055]FIG. 10 is a perspective view showing another embodiment of theinvention concerning a wiring sheet and a wire-cutting method;

[0056]FIG. 11 is an explanatory view showing an important portion ofanother embodiment of an electric distribution box of the invention;

[0057]FIG. 12 is a perspective view showing another embodiment of ahousing member of the invention;

[0058]FIG. 13 is an exploded, perspective view showing one relatedelectric distribution box.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Wiring sheets, an electric distribution box and a wire-cuttingmethod, embodying the present invention, will now be described in detailwith reference to the drawings.

[0060] FIGS. 1 to 9 show one preferred embodiment of the invention,showing the wiring sheets, the electric distribution box andwire-cutting method.

[0061] Referring to the upper and lower sides of wiring sheets 10 and20, that side at which electrical contact portions 37 of bus bars 30project from the wiring sheet 20 is the lower side as shown in FIGS. 1and 2. FIGS. 1 and 2 show the lower side of the wiring sheet 20. Thatside at which electrical contact portions 36 of bus bars 30 project fromthe wiring sheet 10 is the upper side as shown in FIGS. 1, 2, 4 and 5.

[0062] Referring to various directions of the electric distribution box1 with reference to FIG. 6, that side at which an electronic unit 5 isdisposed in a distribution box body 70 is the upper side, and that sideat which support members 100 of a synthetic resin are mounted on thedistribution box body 70 is the lower side. That side at which a cover90 is provided on a fuse block 80 is the front side, and that side atwhich a side wall 72 b of the distribution box body 70 is disposed isthe rear side. The direction in which opposed side walls 72 c and 72 aof the distribution box body 70 face each other is a left-rightdirection.

[0063] In this specification, the definitions “upper and lower”, “frontand rear” and “right and left” are given for convenience, that is, forthe purpose of describing the various portions, and these do not alwayscoincide with their corresponding directions when the wiring sheets andthe electric distribution box are actually used and when the method ofcutting wire is actually carried out.

[0064] As shown in FIGS. 1 and 4, the two wiring sheets 10 and 20 arecombined together, and in this condition the two wiring sheets areprovided within a receiving portion 73 of the distribution box body 70shown in FIG. 6. As shown in FIGS. 4 and 5, bus bars 30 are mounted onthe upper wiring sheet 10 on which a housing member 50 and theelectronic unit 5 (FIG. 6) are mounted. As shown in FIGS. 1 and 2, busbars 30 are mounted on the lower wiring sheet 20 to which the upperwiring sheet 10 is connected. As shown in FIGS. 4 and 5, anotherelectronic unit 4 is mounted in a receiving portion 20P of the wiringsheet 20 shown in FIG. 1.

[0065] As shown in FIG. 1, metal bus bars 30E, 30F, 30G and 30H, havingtheir respective electrical contact portions 37E, 37F, 37G and 37H ofvarious shapes, are mounted on the wiring sheet 20 made of a syntheticresin. A portion of each of the bus bars 30F and 30H is bent into agenerally crank-shape, and the electrical contact portions 37F and 37Hare formed at the bus bars 30F and 30H, respectively. The electricalcontact portions 37G and 37H of the bus bars 30G and 30H are smaller inwidth than the electrical contact portions 37E and 37F of the bus bars30E and 30F.

[0066] As shown in FIGS. 1, 2, 4 and 5, metal bus bars 30A, 30B, 30C and30D, having their respective electrical contact portions 36A, 36B, 36Cand 36D of various shapes, are mounted on the wiring sheet 10 made of asynthetic resin. The electrical contact portions 36C and 36D of the busbars 30C and 30D are smaller in width than the electrical contactportions 36A and 36B of the bus bars 30A and 30B.

[0067] For forming the various bus bars, for example, elongate metalterminal blanks of various shapes are formed from a flat metal sheet bythe use of a pressing machine or the like, and thereafter each metalterminal blank is formed into a predetermined shape by a pressingoperation such as a bending operation.

[0068] The bus bars 30A, 30B, 30C, 30D, 30E, 30F, 30G and 30H of thevarious shapes are representatively designated by reference numeral 30.Terminal portions 33F of the bus bars 30 are representatively designatedby reference numeral 33. The electrical contact portions 36A, 36B, 36Cand 36D of the various shapes are representatively designated byreference numeral 36. The other electrical contact portions 37E, 37F,37G and 37H of the various shapes are representatively designated byreference numeral 37.

[0069] As shown in FIGS. 1 to 6, each of the bus bars 30 is tin-platedas at P. By thus applying a plating treatment to the various bus bars30, the terminal portions 33, the electrical contact portions 36 and 37,tuning-fork terminal portions 38 or press-contacting terminal portions39, when electrically contacted with their mating terminals or matingelectrical contact portions, their contact stability and connectabilityare enhanced. And besides, the electrically-connectable portions areprevented from oxidation.

[0070] When the plating treatment is applied to at least one or both ofthe two mating terminal portions or electrical contact portions in orderto enhance the weldability and the contact stability, the corrosionresistance of the terminal portion or the electrical contact portion areenhanced. When each elongate bus bar 30 is beforehand coated with aplating material P such as tin-plating P over an entire length thereof,the bus bar 30 is prevented from corrosion. As a result, in use, eachbus bar 30 can maintain the stable performance for a long period oftime.

[0071] Tin has a silver-white color and a metallic luster, and areexcellent in ductility and malleability. Tin is oxidized when it isheated at high temperature in the atmosphere, but tin will not rust atnormal temperature. Therefore, tin will not lose its luster. Thus, tinhas such a nature that it is hardly changed in the air, and thereforewhen tin-plating is applied to the surface of a shaped member of metalsuch as iron, steel and copper, the corrosion of the shaped metal memberwill not proceed, and the shaped metal member is protected by thetin-plating coating over a long period of time.

[0072] According to the specifications of the wiring sheets and electricdistribution box, the bus bars are not subjected to the platingtreatment such as tin-plating, in which case the bus bars with noplating are used.

[0073] As shown in FIGS. 1 and 2, many holding portions 29 forrespectively receiving the press-contacting terminal portions 39 of themetal bus bars 30, as well as many holding portions 27 for respectivelyreceiving the tab-like electrical contact portions 37 of the metal busbars 30, are formed at the reverse sides of the synthetic resin-moldedwiring sheets 10 and 20. A plurality of generally-cylindrical fixingportions 25 and 26 are formed on the reverse side of a base plateportion 21 of the wiring sheet 20 so that the wiring sheets 10 and 20and so on can be positively fixed to a base wall of the distribution boxbody through these fixing portions. A fixing hole 25 a is formed in eachof the fixing portions 25, and a fixing hole 26 a is formed in each ofthe fixing portions 26, and a fastening element such as a screw ispassed through the fixing hole 25 a, 26 a.

[0074] As shown in FIG. 2, the press-contacting terminal portions 39(each having, for example, a shape shown in FIG. 3) of the bus bars 30are received in receiving portions 29 a of the holding portions 29,respectively. As shown in FIG. 2, wires 9 are passed through and held inpassage portions 29 b of the holding portions 29, respectively. As shownin FIG. 3, the wire 9 (that is, the wiring member 9) includes a circuitconductor 9 a formed by twisting a plurality of thin soft copper wireelements together, and the circuit conductor 9 a is covered with aninsulating sheath 9 b made of polyvinyl chloride, so that the wire 9 hasa linear body of a generally round cross-section.

[0075] When the wires 9 are installed on the wiring sheets 10 and 20,the wires 9 are suitably bent around side surfaces 24 a of cylindricalprojected portions 24 formed on the wiring sheet 20, as shown in FIG. 2,and by doing so, the direction of extending of each wire 9, installed onthe wiring sheet 20, can be changed. The wiring sheets 10 and 20 areused as wiring boards.

[0076] As shown in FIG. 4, the upper wiring sheet 10 includes a boardportion 11 having a generally-rectangular shape in horizontal, andvertical side plate portions 12 ₁, 12 ₂ and 12 ₃ formed at a peripheraledge portion of the board portion 11. A plurality of wires 9 areinstalled on the wiring sheet 10 as shown in FIG. 5. End portions 9 c ofthe plurality of wires 9, forming circuits, are collectively disposed atone side plate portion 12, of the side plate portion 12 of the wiringsheet 10. As shown in FIG. 5, the end portions 9 c of the majority ofthe wires 9 are collectively disposed at one side plate portion 12 ₁ ofthe wiring sheet 10.

[0077] As shown in FIG. 1, the lower wiring sheet 20 includes a boardportion 21 having a generally-rectangular shape in horizontal, andvertical side plate portions 22 ₁, 22 ₂ and 22 ₃ formed at a peripheraledge portion of the board portion 21. A plurality of wires 9 areinstalled on the wiring sheet 20 as shown in FIG. 2. End portions 9 c ofthe plurality of wires 9, forming circuits, are collectively disposed atone side plate portion 22, of the side plate portion 22 of the wiringsheet 20. As shown in FIGS. 1 and 2, the end portions 9 c of themajority of the wires 9 are collectively disposed at one side plateportion 22 ₁ of the wiring sheet 20.

[0078] The end portions 9 c of the plurality of wires 9, forming thecircuits, are thus collectively disposed at the one side plate portion12 ₁, 22 ₁ of the wiring sheet 10, 20. With this construction, forexample, there can be easily carried out an operation in which the wires9 are cut along the one side plate portion 12 ₁, 22 ₁ of the wiringsheet 10, 20, so that the circuits, provided with the plurality of wires9, are formed at the wiring sheet 10, 20. Therefore, the circuits,provided with the plurality of wires 9, can be easily and rapidly formedat the wiring sheet 10, 20, and therefore there are provided the wiringsheets 10 and 20 which are excellent in productivity. And besides, thecost of the wiring sheets 10 and 20, as well as the cost of the electricdistribution box 1 (FIGS. 6 and 9) having the wiring sheets 10 and 20mounted therein, is reduced.

[0079] As shown in FIGS. 1, 2, 4 and 5, a plurality of mounting portions22 a for the end portions 9 c of the wires 9, are formed at the one sideplate portion 22 ₁ of the wiring sheet 20, and the end portions 9 c ofthe plurality of wires 9 are fixed to the plurality of mounting portions22 a, respectively. Similarly, a plurality of mounting portions 12 a,corresponding to the end portions 9 c of the wires 9, are formed at theone side plate portion 12 ₁ of the wiring sheet 10, and the end portions9 c of the plurality of wires 9 are fixed to the plurality of mountingportions 12 a, respectively.

[0080] Thus, the plurality of mounting portions 12 a, 22 a are providedat the one side plate portion 12 ₁, 22 ₁ of the wiring sheet 10, 20, andtherefore the end portions 9 c of the plurality of wires 9 arepositively kept retained respectively in the plurality of mountingportions 12 a, 22 a formed in the one side plate portion 12 ₁, 22 ₁ ofthe wiring sheet 10, 20.

[0081] And besides, for example, the wires 9 can be cut at the one sideplate portion 12 ₁, 22 ₁ of the wiring sheet 10, 20, using a cuttingtool (not shown) such as a cutter, and by doing so, the operation forcutting the wires 9, installed on the wiring sheet 10, 20, can becarried out at one time, and therefore the operation for cutting thewires 9 is effected rapidly.

[0082] As shown in FIGS. 1 and 2, each of the mounting portions 22 a,formed at the one side plate portion 22 ₁ of the wiring sheet 20, is inthe form of a groove 22 a having a generally U-shape for holding the endportion 9 c of the wire 9, and the end portion 9 c of the wire 9 ispress-fitted in the generally U-shaped groove 22 a. Similarly, each ofthe mounting portions 12 a, formed at the one side plate portion 12 ₁ ofthe wiring sheet 10, is in the form of a groove 12 a having a generallyU-shape for holding the end portion 9 c of the wire 9, and the endportion 9 c of the wire 9 is press-fitted in the generally U-shapedgroove 12 a.

[0083] Since the end portions 9 c of the plurality of wires 9 arepress-fitted respectively in the plurality of grooves 12 a, 22 a formedin the wiring sheet 10, 20, the plurality of wires 9 are positivelyfixed to the one side plate portion 12 ₁, 22 ₁ of the wiring sheet 10,20 over a long period of time. And besides, when the wire 9 is to becut, for example, by a cutting tool (not shown) so as to form thecircuits (provided with the plurality of wires 9) at the wiring sheet10, 20, the wire 9 will not be flexed, thereby avoiding a trouble suchas the failure to cut the wire 9, and as a result the circuits, providedwith the plurality of wires 9, are easily and positively formed at thewiring sheet 10, 20.

[0084] As shown in FIG. 5, end surfaces 9 d (that is, cutting surfaces 9d formed by the cutting tool (not shown)), formed respectively at theend portions 9 c of the wires 9, are disposed outwardly of the boardportion 11 and vertical side plate portion 12 (formed at the peripheraledge portion of the board portion 11) of the upper wiring sheet 10.Also, end surfaces 9 d (that is, cutting surfaces 9 d formed by thecutting tool (not shown)), formed respectively at the end portions 9 cof the wires 9, are disposed outwardly of the board portion 21 andvertical side plate portion 22 (formed at the peripheral edge portion ofthe board portion 21) of the lower wiring sheet 20 as shown in FIG. 2.

[0085] When the plurality of wires 9 are thus installed on the wiringsheet 10, 20, any of the cutting surfaces 9 d, formed respectively atthe end portions 9 c of the wires 9, is not disposed within a wiringarea 10A, 20A of the wiring sheet 10, 20. The wiring area 20A means awire-installing portion which is provided within the wiring sheet 20,and is defined by the board portion 21 and the side plate portions 22 ₁,22 ₂ and 22 ₃.

[0086] Therefore, the cutting surface 9 d at the end portion 9 c of eachwire 9 will not contact a body portion (not shown) of the bus bar 30,the electrical contact portion 37 or the press-contacting terminalportion 39 provided within the wiring area 10A, 20A of the wiring sheet10, 20, thereby preventing electrical troubles such as theshort-circuiting in the circuits of the wiring sheet 10, 20, andtherefore the reliability of the wiring sheets 10 and 20 is enhanced.

[0087] The wiring sheets 10 and 20 (shown in FIGS. 1 and 4) are receivedwithin the distribution box body 70 as shown in FIG. 6. The cuttingsurfaces 9 d (shown in FIGS. 2 and 5), formed respectively at the endportions 9 c of the wires 9, are protected by the side wall 72 c of thedistribution box body 70 shown in FIG. 6. More specifically, the cuttingsurfaces 9 d, formed respectively at the end portions 9 c of the wires 9as shown in FIGS. 2 and 5, are disposed inwardly of a base wall 71 andone side wall 72 c (formed at a peripheral edge portion of the base wall71) of the distribution box body 70 shown in FIG. 6.

[0088] With this arrangement, the cutting surfaces 9 d, formedrespectively at the end portions 9 c of the wires 9 by the cutting tool,will not be exposed to the exterior of the base wall 71 and side wall 72c of the distribution box body 70. Therefore, electrical troubles suchas an electric leakage are prevented, and there can be provided theelectric distribution box 1 of enhanced reliability.

[0089] Next, a method of cutting wire according to the invention will bedescribed in detail with reference to FIGS. 10 and 11.

[0090]FIGS. 10 and 11 show another embodiment of the inventionconcerning a wiring sheet, an electric distribution box and awire-cutting method. FIG. 10 shows the lower side of the wiring sheet 10i. That side at which electrical contact portions 37 ₁ of bus bars 30,project from the wiring sheet 10 ₁ is the lower side, and that side atwhich electrical contact portions 36 ₁ of bus bars 30, project from thewiring sheet 10 ₁ is the upper side.

[0091] Instead of the wiring sheet 10 shown in FIGS. 1, 2, 4 and 5, thewiring sheet 10 ₁, shown in FIG. 10, can be mounted on the electricdistribution box. The wiring sheet 10, shown in FIGS. 1, 2, 4 and 5, hasgenerally the same construction as that of the wiring sheet 10, shown inFIG. 10. Those portions of the wiring sheet 10 ₁ of FIG. 10 identical tothose of the wiring sheet of FIGS. 1 to 5 will be designated byidentical reference numerals, respectively, and detailed explanationthereof will be omitted.

[0092] The upper wiring sheet 10 ₁ includes a board portion 11 ₁ havinga generally-rectangular shape in horizontal, and vertical side plateportions 12 ₁₁, 12 ₁₂ and 12 ₁₃ formed at a peripheral edge portion ofthe board portion 11 ₁. Wires 9 are installed on the wiring sheet 10 ₁in a complicated manner.

[0093] The bus bars 30 and 30 ₁ are coated with a plating material Psuch as tin-plating P. Referring to a bus bar 30K having a tuning-forkterminal portion 38K, one end portion of a bus bar body 31K of this busbar 30K is bent at generally right angles in a multi-stage manner toform the tuning-fork terminal portion 38K The other end portion of thebus bar body 31K is bent at generally right angles to form apress-contacting terminal portion 39K. Although this bus bar 30K is notsubjected to a plating treatment, those bus bars 30, having tuning-forkterminal portions 38, are coated with tin-plating P.

[0094] Holding portions 19K (each having a passage hole), correspondingrespectively to the press-contacting terminal portions 39K of the busbars 30K, are formed at the board portion 11 ₁ of the wiring sheet 10 ₁.The press-contacting terminal portions 39K of the bus bars 30K arefitted respectively in the holding portions 19K formed at the boardportion 111 of the wiring sheet 10 ₁.

[0095] A mounting portion 31 p in the form of a through hole is formedin the bus bar body 31K Fixing portions 13 ₁, corresponding respectivelyto the mounting portions 31 p, are formed at the board portion 11 ₁ ofthe wiring sheet 10 ₁. The mounting portion 31 p of the bus bar body 31Kis fitted on the fixing portion 13, of the wiring sheet 10 ₁, and thetwo are joined together, for example, by thermal welding, thereby fixingthe bus bar 30K to the wiring sheet 10 ₁.

[0096] Holding portions 17 ₁ for the passage of electrical contactportions 37 ₁ of tab-like bus bars 30 ₁ therethrough are formed at theboard portion 11 ₁ of the wiring sheet 10 ₁. Rectangular through holes17 b for the passage of tab-like terminal portions (projecting from alower wiring sheet) therethrough are formed in the board portion 11 ₁ ofthe wiring sheet 10 ₁ disposed at an upper layer side of the electricdistribution box.

[0097] As shown in FIG. 10, one wire 9 is press-contacted withpress-contacting terminals 39 provided in a projected manner at thewiring sheet 10 ₁, and this single wire 9 is installed over a wiringarea 10A₁ of the wiring sheet 10 ₁. The single wire 9 is fixed to theside plate portion 12 ₁ of the wiring sheet 10 ₁ and holding portions 18₁ and 19 ₁. The single wire 9 is fitted in grooves in the holdingportions 18 ₁ and 19 ₁ and grooves in the side plate portion 12 ₁, sothat this single wire 9 is mounted on the wiring sheet 10 ₁. By doingso, the single wire 9 is positively attached to the wiring sheet 10 ₁.

[0098] A wire 9 is fed from a wire feed portion (not shown) of a wiringapparatus (not shown) such as a wiring machine, and at this time thewiring apparatus (not shown) and the wiring sheet 10 ₁ move relative toeach other in forward, backward, right and left directions, so that thewire 9 is installed on the reverse side of the wiring sheet 10 in acomplicated manner.

[0099] The wire 9 is suitably bent around side surfaces 14 a ofcylindrical projected portions 14 formed on the reverse side of thewiring sheet 10 ₁, and by doing so, the direction of extending of thewire 9, installed on the wiring sheet 10 ₁, can be changed. End portions9 c of the wires 9 are fitted respectively in mounting portions 12 a ₁formed in the side plate portion 12 of the wiring sheet 10 ₁. Themounting portions 12 a ₁ has U-shaped groove.

[0100] Press-contacting terminal portions 39 (each having, for example,a shape shown in FIG. 3) of the bus bars 30 are received in many holdingportions 19 ₁, respectively. As shown in FIG. 3A, the press-contactingterminal portion 39 of the bus bar 30, shown in FIG. 10, includes apress-contacting piece portion having a generally U-shapedpress-contacting slit 39 a formed between a pair of generally parallelpress-contacting blades 39 b. Slanting portions 39 d, generally inwardlyfacing each other, are formed at the pair of plate-like press-contactingblades 39 b, respectively, and an edge portion 39 c is formed at each ofthe slanting portions 39 d. The thickness of each plate-likepress-contacting blade 39 b is gradually decreasing such that the edgeportion 39 c on the slanting portion 39 d is relatively sharp.

[0101] When the wiring member 9, having the circuit conductor 9 aprotected by the insulating sheath 9 b, is pressed against the pluralityof press-contacting terminal portions 39, and is press-connectedthereto, the wiring member 9 is electrically connected to thesepress-contacting terminal portions 39. When the wiring member 9, havingthe circuit conductor 9 a protected by the insulating sheath 9 b, beginsto be press-contacted with the pair of press-contacting blades 39 b ofthe press-contacting terminal portion 39, the insulating sheath 9 b ofthe wiring member 9 begins to be cut by the sharp edge portions 39 c ofthe slanting portions 39 d of the press-contacting blades 39 b.

[0102] When the wiring member 9 is further pressed toward thepress-contacting slit 39 a between the pair of press-contacting blades39 b, the insulating sheath 9 b of the wiring member 9 is cut by thepress-contacting slit portion 39 a of the press-contacting terminalportion 39, and the press-contacting slit portion 39 a of thepress-contacting terminal portion 39 is brought into contact with thecircuit conductor 9 a provided within the insulating sheath 9 b of thewiring member 9, so that the wiring member 9 is electrically connectedto the press-contacting terminal portion 39 as shown in FIG. 3B. Thus,in this press-connecting operation, the operation for removing theinsulating sheath 9 b of the wiring member 9 and the operation forconnecting the circuit conductor 9 a of the wiring member 9 to thepress-contacting terminal portion 39 are carried out at the same time.

[0103] As shown in FIG. 10, portions 9 h of one wire 9 are fixed to theside plate portion 12 ₁ of the wiring sheet 10 ₁, and the portions 9 hof the single wire 9 are cut at the same time by the use of a cuttingtool (not shown), thereby dividing the single wire 9 into a plurality ofwires 9. As a result, a cutting surface 9 d is formed at the end portion9 c of each of these wires 9. The wire-cutting operation is effectedalong one side plate portion 12 ₁₁ of the wiring sheet 10 ₁ by the useof the cutting tool (not shown), so that the operation for installingthe wires 9 on the wiring sheet 10, is finished.

[0104] By doing so, the portions 9 h of one wire 9 can be easily cut.And besides, with this wire-cutting method, the portions 9 h of the wire9 can be cut efficiently and rapidly. Therefore, the efficiency of theprocess of cutting the wire 9 is enhanced.

[0105] The plurality of mounting portions 12 a ₁, corresponding to theportions 9 h of one wire 9, are formed at the one side plate portion 12₁₁ of the wiring sheet 10 having a generally-rectangular shape. Theportions 9 h of one wire 9 are fixed to the plurality of mountingportions 12 a ₁ so as to bent the one wire 9. By thus fixing the singlewire 9 to the wiring sheet 10 ₁, the portions 9 h of the single wire 9can be positively mounted at the mounting portions 12 a ₁ of the oneside plate portion 12 ₁₁ of the wiring sheet 10 ₁.

[0106] The portions 9 h of one wire 9 are fixed to the mounting portions12 a ₁ of the one side plate portion 12 ₁₁ of the wiring sheet 10 ₁, andthen the portions 9 h of the single wire 9 are cut at the same time, andtherefore it is only necessary to effect the cutting operation for thesingle wire 9 at the mounting portions 12 a ₁ of the one side plateportion 12 ₁, of the wiring sheet 10 ₁. Therefore, it is not necessaryto effect the cutting operation for the single wire 9 at variousportions of the wiring sheet 10 ₁. Therefore, the operation for cuffingthe wire 9 can be effected positively and rapidly.

[0107] Each of the mounting portions 12 a ₁ is in the form of agenerally U-shaped groove 12 a ₁. The plurality of U-shaped grooves 12 a₁ for holding the portions 9 h of one wire 9 are formed in the one sideplate portion 12 ₁₁ of the wiring sheet 10 ₁, and the portions 9 h ofthe single wire 9 are press-fitted into these grooves 12 a ₁.

[0108] By doing so, the portions 9 h of one wire 9 are positively fixedto the one side plate portion 12 ₁₁ of the wiring sheet 10 ₁. Therefore,at the time of cutting the portions 9 h of the single wire 9, theportions 9 h of the single wire 9 are prevented from shaking relative tothe wiring sheet 10 ₁, and the cutting operation for the single wire 9is carried out easily and positively.

[0109] One wire 9, laid on the board portion 11 ₁ of the wiring sheet 10₁, is extended to the outside of the side plate portion 12 ₁ formed atthe peripheral edge portion of the board portion 11 ₁, and a portion 9 hof the single wire 9 is folded back to thereby introduce the single wire9 again into the inside of the side plate portion 12 ₁. By doing so, theportion 9 h of the single wire 9 is fixed to the side plate portion 12 ₁of the wiring sheet 10 ₁.

[0110] The wire 9 is fixed in a direction generally perpendicular to theextending direction of the one side plate portion 12 ₁₁ of the wiringsheet 10 ₁, and a portion 9 h of the wire 9 is bent, and then the wire 9is fixed in a direction generally perpendicular to the extending of theone side plate portion 12 ₁₁ of the wiring sheet 10 ₁. This operation isrepeated, so that the single wire 9 is mounted on the one side plateportion 12 ₁₁ of the wiring sheet 10 ₁ as shown in FIG. 10.

[0111] By thus fixing one wire 9 to the side plate portion 12 ₁ of thewiring sheet 10 ₁, the operation for cutting the single wire 9 can beeasily effected. For example, when the cutting operation for one wire 9is to be carried out by the use of the cutting tool (not shown), thecutting tool (not shown) is moved along the outer side of the side plateportion 12 ₁ of the wiring sheet 10 ₁, and as a result the portions 9 hof the single wire 9, disposed at the outside of the side plate portion12 ₁₁ of the wiring sheet 10 ₁, are easily cut. Therefore, the processof cutting the wire 9 is carried out rapidly. When this cutting processis effected, the end portions 9 c of the plurality of wires 9, formingthe circuits, are collectively disposed at one side plate portion 12 ₁₁of the side plate portion 12 ₁ of the wiring sheet 10 ₁.

[0112] In one wire 9 extended to the outside of the side plate portion12 ₁ of the wiring sheet 10 ₁, the plurality of wire portions 9 h,formed by bending this wire 9, are cut at the same time, and cutoffportions 9 k are removed. With this wire-cutting method, troubles, suchas the failure to cut the wire 9, are prevented at the time of cuttingthe wiring member 9. Therefore, the circuits, provided with theplurality of wires 9, can be positively formed at the wiring sheet 10 ₁.And besides, the end portions 9 c of the majority of the wires 9 arecollectively disposed at the one side plate portion 12 ₁₁ of the wiringsheet 10 ₁.

[0113] The installation method, press-contacting method and cuttingmethod for the wires 9, shown in FIGS. 1, 2, 4 and 5, are performedaccording to generally the same procedure as described above for FIG.10.

[0114] There can be used another method of cutting the wire 9, in whichthe portions 9 h of one wire 9 are fixed to the one side plate portion12 ₁₁ of the wiring sheet 10 ₁ as shown in FIG. 10, and then the wiringsheet 101 is received in a distribution box body 70 ₁, and at the sametime the portions 9 h of the single wire 9 are fixed to engagingportions 72 p provided at a side wall 72 c ₁ of the distribution boxbody 70 ₁, and then the plurality of portions 9 h, formed by bending thewire 9, are simultaneously cut, and the plurality of cut-off portions 9k are removed. The engaging portions 72 p having a generally cylindricalshape are formed on and extend upwardly from a base wall 71 ₁ of thedistribution box body 70 ₁.

[0115] By doing so, the portions 9 h of the single wire 9 are positivelyretainingly engaged with the wiring sheet 10 and the distribution boxbody 70 ₁. Therefore, when cutting the portions 9 h of the single wire9, the portions 9 h of the wire 9 are prevented from being much flexed,so that it is not difficult to effect the operation for cutting theportions 9 h of the single wire 9. Therefore, the portions 9 h of thesingle wire 9, retainingly engaged with the wiring sheet 10 ₁ and thedistribution box body 70 ₁, are held in such a condition that theseportions 9 h can be cut positively and easily. After the portions 9 h ofthe wire 9 are cut, the cutoff portions 9K of the wire 9 are removedfrom the distribution box body 70 ₁, for example, by a suctionapparatus.

[0116] Thereafter, the electric distribution box 11 is assembled. Theengaging portions 72 p, shown in FIG. 11, are provided only at thedistribution box body 70 ₁ of the electric distribution box 1 ₁, and arenot provided at the electric distribution box 1 shown in FIG. 6. Exceptthe provision of the engaging portions 72 p and the difference betweenthe side wall 72 c (FIG. 6) and the side wall 72 c ₁ (FIG. 11), theelectric distribution box 1 ₁, shown in FIG. 11, has generally the sameconstruction as that of the electric distribution box 1 shown in FIG. 9.

[0117] The wiring sheets 10 and 20, shown in FIGS. 1, 2, 4 and 5, arereceived in the receiving portion 73 of the distribution box body 70shown in FIG. 6. The process of assembling the electric distribution box1 (shown in FIGS. 6 and 9) will be described in the following.

[0118] As shown in FIG. 6, this electric distribution box 1 has such anassembling structure that external wire harnesses (not shown), providedon the upper side of the distribution box body 70, are electricallyconnected via the plurality of bus bars 30 to the electronic unit 5provided at the upper portion of the interior of the distribution boxbody 70.

[0119] The electronic unit 5 includes an insulating board portion (thatis, a printed circuit board) 5A which is made of a synthetic resin, andhas circuit conductors 5B printed thereon. Electric and electronicparts, including an IC package 5H, a capacitor 5J, relay connectionbases 5K (to which relays (not shown) are connected), a connector 5L andanother connector 5P, are mounted on the insulating board portion 5A.These parts are electrically connected via the circuit conductors madeof a copper foil, thereby forming an electronic control device.

[0120] “IC” means an integrated circuit, and is an abbreviation of“Integrated Circuit”. An IC is a kind of electronic circuit, and manycircuit elements, such as transistors, diodes, resistors and capacitors,are associated on or within one substrate, and are interconnected bywiring, thereby forming the electronic circuit of a high-densitystructure.

[0121] The electronic control unit is often called “ECU”. An electroniccontrol unit includes control member controlled by a computer, andjudgment member. The circuit conductors 5B, printed on the insulatingboard portion 5A made of a synthetic resin, are protected by aninsulating coating 5C which is either transparent or translucent.

[0122] Metal terminals (not shown) are inserted in a connector housing5M made of a synthetic resin, thereby forming the connector 5L. Arectangular opening 5D is formed through that portion of the boardportion 5A disposed in registry with the lower surface of the connector5L. With this construction, the electrical contact portions 36 of thecorresponding bus bars 30 can be connected to the connector 5L from thelower side of this connector.

[0123] Mounting portions (not shown) of the terminals, provided in theconnector 5L, are soldered respectively to the corresponding circuitconductors 5B printed on the insulating board portion 5A, and thereforeare electrically connected to these circuit conductors 5B. Thus, theconnector 5L, shown in FIG. 6, is used as a vertically-mounting-typeconnector for PCB. “PCB” means “printed circuit board”.

[0124] The other connector 5P includes male metal terminals 5T, and aconnector housing 5Q made of a synthetic resin. The male terminals 5Tare electrically connected respectively to the corresponding circuitconductors 5B printed on the insulating board portion 5A.

[0125] As shown in FIGS. 5 and 6, the tab-like terminal portion 33 (FIG.5) is formed at one end of the metal bus bar 30, and the tab-likeelectrical contact portion 36 is formed at the other end of the metalbus bar 30. The tab-like terminal portions 33, projecting from orpassing through a power module 6, and the electrical contact portions36, projecting from the synthetic resin-molded wiring sheet 10, extendupwardly relative to the synthetic resin-molded distribution box body 70(FIG. 6) on which these are mounted. “A module” means is a unit formingpart of an apparatus, a machine or a system, and is formed as afunctional unit.

[0126] As shown in FIGS. 4 and 5, a projecting piece portion 55 extendsfrom one side of a peripheral wall 52 of the synthetic resin-moldedhousing member 50, and the housing body 51 and the projecting pieceportion 55 are molded integrally with each other, using a syntheticresin. The projecting piece portion 55 is in the form of a thinplate-like member of a generally inverted L-shape.

[0127] As shown in FIGS. 4 and 5, a step portion 55 j is formed on athinned portion 55 n of the projecting piece portion 55 to form athickened portion 55 m on the projecting piece portion 55 of the housingmember 50. The thinned portion 55 n and thickened portion 55 m of theprojecting piece portion 55 are molded integrally with each other, usingthe same synthetic resin. Cavities 56 for respectively passing theelectrical contact portions 36 of the bus bars 30 therethrough areformed through the thickened portion 55 m of the projecting pieceportion 55. A cavity means a vacant space, a hollow portion or a throughhole. A separate molded member, serving as a separate thickened portion(55 m), can be mounted on the projecting piece portion 55.

[0128] When the synthetic resin-molded housing member 50 is mounted onthe distribution box body 70 of the electric distribution box 1, thepower module 6 and the synthetic resin-molded wiring sheet 10, thetab-like metal terminal portions 33 project into a receiving portion 53of the housing body 51 of the housing member 50, and is receivedtherein, thereby forming a connector portion 3. As shown in FIGS. 4 and5, the terminal portions 33 are disposed within an opening 54 in thereceiving portion 53 of the housing body 51.

[0129] The connector portion 3 is formed, and also the electricalcontact portions 36, projecting upwardly from the wiring sheet 10, arepassed respectively through the cavities 56 formed through theprojecting piece portion 55 of the housing member 50. At this time, theelectrical contact portions 36, which have not been properly positioned,and therefore have been tilted, are inserted respectively into thecavities 56 in the projecting piece portion 55 of the housing member 50as shown in FIGS. 4 to 6. As a result, the plurality of electric contactportions 36 are corrected in posture, and are arranged generally on astraight line. Also, the thus corrected electrical contact portions 36are electrically connected respectively to the terminals (not shown) ofthe connector 5L (FIG. 6) mounted on the electronic unit 5.

[0130] As shown in FIG. 6, the electronic unit 5, the wiring sheet 10,etc., are mounted within the receiving portion 73 of the distributionbox body 70. Part of the housing member 50, such as the projecting pieceportion 55 of the housing member 50, are disposed within thedistribution box body 70, while the housing body 51 of the housingmember 50 is exposed to the exterior of the distribution box body 70 asshown in FIG. 9. The connector portion 3 is provided at the outside ofthe electric distribution box 1 so that the external wire harnesses (notshown) can be easily connected to this connector portion 3.

[0131] In order that the power module 6 can be easily mounted on theupper wiring sheet 10, a stepped portion 11B is formed at the boardportion 11 of the upper wiring sheet 10. Also, other base plate portion11A, corresponding in shape to a base plate portion 6A of the powermodule 6, extends from the board portion 11 of the wiring sheet 10 insuch a manner that the other base plate portion 11A is disposed at alevel lower than the upper base plate portion 11. The upper base plateportion 11 and lower other base plate portion 11A of the wiring sheet 10are interconnected by the stepped portion 11B, and are molded integrallywith each other.

[0132] As shown in FIGS. 4 and 5, positioning portions 15B of agenerally cylindrical shape are formed on the other base plate portion11A of the upper wiring sheet 10. The positioning portions 15B, formedon the other base plate portion 11A of the wiring sheet 10, projectupwardly beyond the base plate portion 6A of the power module 6. Inorder that the housing member 50 can be easily mounted on the powermodule 6 and the upper wiring sheet 10, the positioning portions 15Bextend upwardly respectively through circular holes (not shown) formedin the base plate portion 6A of the power module 6. As shown in FIG. 4,a plurality of positioning portions 55 b (each in the form of agenerally-circular hole), corresponding respectively to the plurality ofpositioning portions 15B, are formed in the projecting piece portion 55of the housing member 50.

[0133] In order that the housing member 50 can be mounted on the boardportion 11 of the upper wiring sheet 10 in a properly positioned manner,a plurality of positioning portions 11 h having a generally-cylindricalshape are formed on the board portion 11 of the wiring sheet 10 as shownin FIGS. 4 and 5. A plurality of positioning portions 55 h (each in theform of a generally-circular hole), corresponding respectively to theplurality of positioning portions 11 h, are formed in the projectingpiece portion 55 of the housing member 50.

[0134] In order that the electronic unit 5 (shown in FIG. 6) can bepositively mounted within the electric distribution box 1, a pluralityof fixing portions 15A, each having a fixing hole 15A_(L), are formed onthe upper side of the board portion 11 of the wiring sheet 10 as shownin FIGS. 4 and 5. Also, the plurality of fixing portions 15B, eachhaving a fixing hole 15B_(L), are formed on the other base plate portion11A of the wiring sheet 10.

[0135] The fixing portions 15B, formed on the upper side of the otherbase plate portion 11A of the wiring sheet 10, serve also as thepositioning portions 15B by which the mounting directions of the powermodule 6 and housing member 50 can be easily recognized. A plurality offixing portions (each having a generally-cylindrical fixing hole5V_(L)), corresponding respectively to the plurality ofgenerally-cylindrical fixing portions 15A and 15B, are formed in thebase portion 5A of the electronic unit 5 as shown in FIG. 6.

[0136] The electrical contact portions 36, projecting upwardly from theupper wiring sheet 10 and the projecting piece portion 55 of the housingmember 50, are connected respectively to the terminals (not shown) ofthe connector 5L provided at the electronic unit 5, and also the fixingholes 15A_(L) of the fixing portions 15A (formed on the board portion 11of the wiring sheet 10) and the fixing holes 15B_(L) of the fixingportions 15B (formed on the other base plate portion 11A of the wiringboard 10) are aligned with the respective fixing holes 5V_(L) formed inthe board portion 5A of the electronic unit 5. Then, fastening elements(not shown), such as screws, are inserted respectively into the fixingholes 5V_(L) formed in the board portion 5A of the electronic unit 5,and further are passed respectively through the corresponding fixingholes 15A_(L) and 15B_(L) of the fixing portions 15A and 15B (The fixingportions 15A are formed on the board portion 11 of the wiring sheet 10,and the fixing portions 15B are formed on the other base plate portion11A). Further, for example, screw portions (not shown) of thesefastening elements are threaded respectively into the fixing holes 25 aof the fixing portions 25 shown in FIGS. 1 and 2, and by doing so, theelectronic unit 5 is positively fixed to the wiring sheets 10 and 20.

[0137] As shown in FIG. 4, a plurality of fixing portions 55 d (each inthe form of a generally-circular hole) are formed in the projectingpiece portion 55 of the housing member 50, and a plurality of fixingportions 6D (each in the form of a generally-circular hole) are formedin the base plate portion 6A of the power module 6. A plurality of otherfixing portions (not shown) of a generally-cylindrical shape,corresponding respectively to the fixing portions 6D and alsorespectively to the fixing portions 55 d, are formed on the other baseplate portion 11A of the wiring sheet 10. As shown in FIGS. 1 and 2, thefixing portions 26 of a generally-cylindrical shape are formed on theboard portion 21 of the lower wiring sheet 20, and the electronic unit 4is provided at the lower side of the wiring sheet 20, andgenerally-cylindrical fixing portions (not shown) (each in the form of agenerally-circular hole) are formed in a base plate portion of theelectronic unit 4. Elongate fastening elements (not shown), such asscrews, are passed through these fixing portions, and for example, screwportions of these fastening elements are threaded respectively intofixing portions (not shown) formed on the bottom wall 71 of thedistribution box body 70 (FIG. 6), and by doing so, the housing member50, the power module 6, the upper wiring sheet 10, the lower wiringsheet 20 and the electronic unit 4 are positively fixed to thedistribution box body 70.

[0138] Instead of the synthetic resin-molded housing member 50 shown inFIGS. 4 to 6, a synthetic resin-molded housing member 50 ₁, shown inFIG. 12, can be mounted in the electric distribution box. FIG. 12 showsanother embodiment of the housing member. Those portions of the housingmember 50 ₁ of FIG. 12 identical to those of the housing member 50 ofFIGS. 4 to 6 will be designated by identical reference numerals,respectively, and detailed explanation thereof will be omitted.

[0139] The housing member 50 ₁, shown in FIG. 12, includes a housingbody 51, a projecting piece portion 55 ₁ extending from one end of thehousing body 51, and a holding member 40 which is mounted on theprojecting piece portion 55 ₁, and has cavities 46.

[0140] A plurality of juxtaposed through holes 53 b for the passage ofthe terminal portions of the various bus bars therethrough are formedthrough a base wall 52 b of the housing body 51 ₁. The projecting pieceportion 55 ₁ of the housing member 50 ₁, shown in FIG. 12, is in theform of a rectangular plate smaller in size than the projecting pieceportion 55 of the housing member 50 shown in FIGS. 4 to 6, and thisprojecting piece portion 55 ₁ extends from one end of the base wall 52 bof the housing body 51 (FIG. 12).

[0141] Instead of the thickened portion 55 m on the projecting pieceportion 55 of the housing member 50 shown in FIGS. 4 and 5, agenerally-rectangular window-like opening 55 m ₁ is formed in theprojecting piece portion 55 ₁ of the housing member 50 ₁, and theholding member 40, made of a synthetic resin, is mounted in this opening55 m ₁.

[0142] The holding member 40 includes an elongate thinned portion 45 nin the form of a generally-rectangular plate, and a thickened portion 45m of a generally rectangular parallelepiped shape formed on andprojecting from the thinned portion 45 n. The plate-like thinned portion45 n and the thickened portion 45 m of a generally rectangularparallelepiped shape are molded integrally with each other, using thesame synthetic resin.

[0143] The plurality of cavities 46 (each in the form of a rectangularhole) are formed in the thickened portion 45 m of the holding member 40.Each of the cavities 46 is in the form of a through hole having aninsertion portion 47 and an opening 48, and the electrical contactportions of the associated bus bars are passed through the plurality ofcavities 46, respectively.

[0144] A small tapering surface is formed at the insertion portion 47 ofeach cavity 46 in the holding member 40. Since the tapering surface 47 ais formed at the insertion portion 47 of the cavity 46, the electricalcontact portions of the plurality of bus bars can be easily insertedinto the plurality of cavities 46, respectively.

[0145] The holding member 40 is formed as a small injection moldedproduct made of a synthetic resin, and therefore the holding members 40,having the cavities 46 each having the small tapering surface 47 a, canbe mass-produced precisely and rapidly.

[0146] As shown in FIG. 5, slanting surfaces 36 k are formed at a distalend 36 j of a straight portion 36 h of each of the electrical contactportions 36 so that the plurality of electrical contact portions 36 canbe simultaneously easily inserted respectively into the plurality ofcavities 56 even when any or all of the tab-like electrical contactportions 36 are tilted in the direction of the thickness of theseelectrical contact portions 36.

[0147] As shown in FIGS. 4 and 12, guide portions 52 h are formed at theopposite ends of the housing member 50, respectively, and guidereceiving portions 76, corresponding respectively to these guideportions 52 h, are formed respectively at the opposed side walls 72 aand 72 c of the distribution box body 70 as shown in FIG. 6.

[0148] As shown in FIGS. 6 and 9, each of the guide receiving portions76 of the distribution box body 70 has a guide groove 76 of a generallyT-shaped cross-section, and each of the guide portions 52 h of thehousing member 50 includes a plate-like guide piece portion 52 hcorresponding to the guide groove 76, as shown in FIGS. 4 and 12.Support portions 52 j are formed on and project outwardly from theperipheral wall 52 of the housing member 50, and the guide pieceportions 52 h of the housing member 50 are formed on outer edges ofthese support portions 52 j, respectively.

[0149] As shown in FIG. 6, each of the guide receiving portions 76 ofthe distribution box body 70 includes a frame portion 76 b extendingoutwardly from the side wall 72 a, 72 c of the distribution box body 70,and an elongate narrow groove corresponding to the support portion 52 j(FIGS. 4 and 12) of the housing member 50.

[0150] As shown in FIG. 6, the connector portion 3 and the electronicunit 5 are juxtaposed to each other in adjoining relation to each otherat the upper layer side of the distribution box body 70 where theconnector portion 3 and the electronic unit 5 are provided. Theconnector portion 3 and the electronic unit are juxtaposed to each otherabove the wiring sheet 10 mounted in the receiving portion 73 of thedistribution box body 70.

[0151] In the electric distribution box 1 of this arrangement structure,the electronic unit 5 can be easily mounted on the distribution box body70. When connecting the connectors (not shown) of the external wireharnesses (not shown) to the connector portion 3 of the electricdistribution box 1 shown in FIG. 1, this connecting operation can becarried out easily.

[0152] As shown in FIGS. 6 and 9, the fuse block 80 is provided at thefront side of the electric distribution box 1. The fuse box is ablock-like part in which a plurality of fuses are mounted in a matingmounting member (such as a housing, a base or a holder) to form a unit.

[0153] The fuse block 80 includes the synthetic resin-molded front cover90 for protecting the fuses (not shown). This front cover 90 includes acover body 91, a pair of hinge portions 92 detachably connected to afuse block body 81, and an operating portion 93 which is provided at alower side of the cover body 91 so as to enable the front cover 90 to beeasily opened and closed relative to the synthetic resin-molded fuseblock body 81.

[0154] The pair of hinge portions 92, formed at the upper side of thefront cover 90, are connected respectively to a pair of hinge portions82 formed at the front side of the fuse block body 81, and by doing so,the front cover 90 is mounted on the fuse block body 81 so as to beopened and closed. Since the front cover 90 is thus mounted on the frontside of the fuse block body 81 so as to be opened and closed, themaintenance, such as the exchange of the fuses (not shown) providedwithin the fuse block body 81, can be carried out easily.

[0155] A pair of retaining portions 88 (each having a retainingprojection 88) are formed at a lower portion of the front side of thefuse block body 81, while a pair of retaining portions 89 (each having aretaining projection 89) are formed at an upper portion of the frontside of the fuse block body 81. A pair of engagement portions 78 (eachhaving an engagement hole 78 of a rectangular shape), correspondingrespectively to the pair of retaining portions 88 formed at the lowerportion of the front side of the fuse block body 81, are provided at alower portion of the front side of the distribution box body 70. A pairof engagement portions 59 (each having an engagement hole 59 of arectangular shape), corresponding respectively to the pair of retainingportions 89 formed at the upper portion of the front side of the fuseblock body 81, are provided at a front wall 52 f of the housing member50.

[0156] The pair of engagement portions 78, provided at the lower portionof the front side of the distribution box body 70, are retaininglyengaged respectively with the pair of retaining portions 88 provided atthe lower portion of the front side of the fuse block body 81, so thatthe fuse block body 81 is positively mounted on the distribution boxbody 70. The pair of retaining portions 89, provided at the upperportion of the front side of the fuse block body 81, are retaininglyengaged respectively with the pair of engagement portions 59 provided atthe front wall 52 f of the housing member 50, so that the housing member50 is attached to the distribution box body 70 and the fuse block 80mounted on the distribution box body 70.

[0157] The plurality of layers of tuning-fork terminal portions 38(shown in FIG. 1) are disposed within the fuse block body 81 shown inFIGS. 6 and 9. The plurality of layers of tuning-fork terminal portions38 are formed respectively by the extension portions of the various busbars 30.

[0158] When the fuse block 80, having the plurality of blade-type fuses(not shown) received therein, is attached to the front side of thedistribution box body 70 as shown in FIG. 6, tab terminals (not shown)of the blade-type fuses within the fuse block body 81 are electricallyconnected respectively to the plurality of layers of tuning-forkterminal portions 38 shown in FIG. 1.

[0159] Thus, in the electric distribution box 1 (FIG. 6), the fuse block80 (FIG. 6), having the blade-type fuses (not shown) received therein,is used, and the tab terminals (not shown) of the blade-type fuses areelectrically connected respectively to the plurality of layers oftuning-fork terminal portions 38 shown in FIG. 1. Therefore, theplurality of blade-type fuses (not shown) can be easily and rapidlyprovided in the electric distribution box 1. Therefore, the efficiencyof the operation for mounting the blade-type fuses (not shown) in theelectric distribution box 1 is enhanced.

[0160] According to the specification of the electric distribution box,other terminals (for example, tab-like terminals or female terminals)than the plurality of layers of tuning-fork terminal portions 38 can beused.

[0161] A synthetic resin-molded upper cover 60, shown in FIGS. 7 and 8,is attached to the distribution box body 70 (shown in FIG. 6), so thatthe electric distribution box 1 is assembled as shown in FIG. 9.

[0162] As shown in FIGS. 7 and 8, the upper cover 60 includes agenerally-rectangular top wall 61, and side walls 62 a, 62 b, 62 c and62 d formed at a peripheral edge portion of the top wall 61. The uppercover 60 has a receiving portion 63 therein as shown in FIG. 8. Agenerally-rectangular opening 65, corresponding to the connector 5P ofthe electronic unit 5, is formed through the top wall 61 of the uppercover 60 as shown in FIGS. 7 and 8.

[0163] As shown in FIGS. 7 and 8, a rib 65 a is formed at a peripheraledge of the opening 65 in the upper cover 60. A guide rib 65 b extendsfrom the rib 65 a (formed at the peripheral edge of the opening 65 inthe upper cover 60) into the interior of the upper cover 60. The rib 65a corresponds in shape to an upper end portion 5R of the connectorhousing 5Q of the connector 5P shown in FIG. 6. The guide rib 65 b,shown in FIGS. 7 and 8, corresponds in shape to a side wall portion 5Sof the connector housing 5Q of the connector 5P shown in FIG. 6.

[0164] As shown in FIG. 7, a plurality of generally T-shaped projections62 t are formed on the side wall 62 d of the upper cover 80, and also apair of windows 62 w are formed in this side wall 62 d. Ribs 61 a and 62b which intersect one another lengthwise and widthwise are formed on theinner surface of the top wall 61 of the upper cover 60 to increase thestrength of the upper cover 60.

[0165] As shown in FIGS. 7 and 8, a plurality of guide portions 67 areformed on the side walls 62 a, 62 b and 62 c of the upper cover 60, anda plurality of guide portions 77, corresponding respectively to theguide portions 67, are formed on the side walls 72 a, 72 b and 72 c ofthe distribution box body 70 as shown in FIG. 6. Also, a plurality offrame-like projections 72 h are formed on the side walls 72 a, 72 b and72 c of the distribution box body 70.

[0166] As shown in FIG. 6, each of the guide receiving portions 77 ofthe distribution box body 70 has a guide groove 77 of a generallyT-shaped cross-section, and each of the guide portions 67 of the uppercover 60 includes a plate-like guide piece portion 67 corresponding tothe guide groove 77, as shown in FIGS. 7 and 8.

[0167] Support portions 67 a are formed on and project outwardly fromthe side walls 62 a, 62 b and 62 c of the upper cover 60, and the guidepiece portions 67 of the upper cover 60 are formed on outer edges ofthese support portions 67 a, respectively. As shown in FIG. 6, each ofthe guide receiving portions 77 of the distribution box body 70 includesa frame portion 77 b extending outwardly from the side wall 72 a, 72 b,72 c of the distribution box body 70, and an elongate narrow groove 77 a(FIG. 6) corresponding to the support portion 67 a of the upper cover60.

[0168] As shown in FIGS. 7 and 8, retaining portions 69 (each having aretaining projection 69) are formed on the side walls 62 a, 62 b and 62c of the upper cover 60. Engagement portions 79 (each having anengagement projection (not shown)), corresponding respectively to theretaining portions 69, are formed on the side walls 72 a, 72 b and 72 cof the distribution box body 70 shown in FIG. 6.

[0169] After the electronic unit 5 is mounted within the distributionbox body 70 (FIG. 6), the cover 60 (shown in FIG. 7) is fitted on thedistribution box body 70, and is attached thereto, so that the electricdistribution box 1 is assembled as shown in FIG. 9.

[0170] At this time, the retaining portions 69 of the cover 60 (shown inFIG. 7) are retainingly engaged respectively with the engagementportions 79 of the distribution box body 70 shown in FIG. 6, and as aresult the cover 60 is positively attached to the distribution box body70 in such a manner that the cover 60 will not shake relative to thedistribution box body 70. At the same time, a plurality of engagementportions 62 k, provided at the side wall 62 d of the cover 60 shown inFIGS. 7 and 8, are engaged respectively with a plurality of retainingportions 52 k provided at the peripheral wall 52 of the housing member50 shown in FIGS. 4 and 12.

[0171] Thereafter, the connectors of the external wire harnesses (notshown) are electrically connected to the connector portion 3 of theelectric distribution box 1 shown in FIG. 9, and also the connectors ofthe other external wire harnesses (not shown) are connected to theconnector portion 5P of the electric distribution box 1. The electricdistribution box 1 is used as a junction box (abbreviated as “J/B”). Theelectric distribution box can also be used, for example, as a relay box(abbreviated as “R/B”) or the like.

[0172] Although the present invention has been shown and described withreference to specific preferred embodiments, various changes andmodifications will be apparent to those skilled in the art from theteachings herein. Such changes and modifications as are obvious aredeemed to come within the spirit, scope and contemplation of theinvention as defined in the appended claims.

What is claimed is:
 1. A wiring sheet for installing a plurality ofwires thereon, comprising: a side plate portion, at which end portionsof the wires forming circuits are collectively disposed.
 2. The wiringsheet as set forth in claim 1, wherein a plurality of mounting portionsare formed on the side plate portion; and wherein the end portions ofthe wires are fixed to the plurality of mounting portions, respectively.3. The wiring sheet as set forth in claim 2, wherein each of themounting portions has a groove shape for holding the end portion of eachof the wires.
 4. The wiring sheet as set forth in claim 1, furthercomprising a board portion placed horizontally, wherein the side plateportion is vertically formed at a peripheral portion of the boardportion; and wherein the end portions of the wires are disposed outsideof the board portion and the side plate portion of the wiring sheet. 5.An electric distribution box, comprising: a wiring sheet for installinga plurality of wires thereon, including: a side plate portion, at whichend portions of the wires forming circuits are collectively disposed;and a main body, housing the wiring sheet therein, and having a sidewall for protecting the end portions of the plurality of wires exposedfrom the side plate portion.
 6. The electric distribution box as setforth in claim 5, wherein the main body has a base wall on which thewiring sheet is placed; wherein the side wall is formed at a peripheralportion of the base wall; and wherein the end portions of the wires aredisposed inside of the base wall and the side wall of the main body. 7.The electric distribution box as set forth in claim 5, wherein aplurality of mounting portions are formed on the side plate portion; andwherein the end portions of the wires are fixed to the plurality ofmounting portions, respectively.
 8. The electric distribution box as setforth in claim 5 wherein each of the mounting portions has a groove forholding the end portion of each of the wires.
 9. The electricdistribution box as set forth in claim 5, wherein the wiring sheetincludes a board portion placed horizontally; wherein the side plateportion is vertically formed at a peripheral portion of the boardportion; and wherein the end portions of the wires are disposed outsideof the board portion and the side plate portion of the wiring sheet. 10.A method of cutting wires, comprising the steps of: installing the wireson a wiring sheet; fixing portions of the wires to a side plate portionof the wiring sheet; and cutting the portions of the fixed wires so asto divide into a plurality of end portions of the wires so that circuitsformed by the cut wires are provided.
 11. The method as set forth inclaim 10, wherein a plurality of mounting portions are formed on theside plate portion; and wherein the end portions of the wires are fixedto the plurality of mounting portions, respectively.
 12. The method asset forth in claim 11, wherein each of the mounting portions has agroove for holding the end portion of each of the wires.
 13. The methodas set forth in claim 10, wherein the wiring sheet has a board portionplaced horizontally, wherein the side plate portion is vertically formedat a peripheral portion of the board portion; and wherein the endportions of the wires are disposed outside of the board portion and theside plate portion of the wiring sheet.
 14. The method as set forth inclaim 10, further comprising the steps of: housing the wiring sheet in amain body of an electric distribution box after performing the fixingstep; and fixing portions of the wires to a side wall of the main body.15. The method as set forth in claim 10 wherein the portions of thewires extended to the outside of the side plate portion are cutsimultaneously in the cutting step so that circuits formed by the cutwires are provided.